1. Field of the Invention
The present invention relates to a nut member that supports and adjusts, for example, a vehicle light.
An adjustment mechanism for adjusting the optical axis of existing lights, such as vehicle headlamps or fog lamps (hereinafter referred to as “lamp members”), includes a screw which is a male screw, and a self-locking nut serving as a female screw, on its back side (see PTL 1, below). The self-locking nut includes a flange and leg pieces. The flange has an axial hole penetrating therethrough. The leg pieces of the self-locking nut are fastened to and the flange of the self-locking nut is supported on the back side of a reflector of a lamp member and a screw is pushed into the axial hole. While the screw is pushed into the axial hole, the screw helically cuts the inner circumferential surface of the axial hole using its screw thread to engrave a female screw on the inner circumferential surface of the axial hole. When the screw is rotated in this state, the self-locking nut moves back and forth relative to the screw. The movement of the self-locking nut changes the angle of the reflector, whereby the optical axis of the lamp member is adjusted.
2. Description of the Related Art
[PLT] Japanese Unexamined Patent Application Publication No. 2014-32742
As described above, however, in this adjustment mechanism, a female screw is engraved on the inner circumferential surface of the axial hole as a result of the screw thread of the screw helically cutting the inner circumferential surface of the axial hole. Thus, chips may accumulate in and adhere to the axial hole. When the optical axis is adjusted in this state, the chips may hinder the screw from rotating and increase torque of the screw, so that the adjustment of the optical axis may be rendered difficult.